Until a few years ago, overrunning roller clutches depended exclusively upon the compression force of the roller energizing springs to retain the rollers in the cage during shipping and handling. In such conventional designs, the rollers are pushed against cage crossbars located in front of the rollers by the compression of the energizing springs between the rollers and cage crossbars located behind the rollers. To install such a clutch, the clutch cage and retained rollers are first pushed axially onto the cam race, and then rotated slightly so that reaction ears on the cage lock to the cam race. These may be seen at 40A and 40B in co-assigned U.S. Pat. No. 4,679,676 to King et al. Then, the pathway race is added by with an axial push and twist, the so called "ringing on" method, which shifts the rollers back along the cam race cam ramps and away from the cage crossbars, compressing the springs further. There are two great drawbacks to this system. The most serious is was the fact that the energizing springs aren't particularly strong, even in their most highly compressed state. They are even less strong in their less compressed, shipping state, and roller retention is accordingly weak. Furthermore, roller travel, the back and forth rolling of a roller on its cam ramp that occurs during clutch operation, is limited by the proximity of the cage crossbars in front of the rollers, which must be fairly close to the rollers.
Newer designs have totally divorced roller retention from the compression force of the energizing springs. One approach, shown in co-assigned U.S. Pat. No. 4,724,940 to Lederman, traps each roller between the end of the spring and a crossbar through the use of a releasable spring latch. The spring latch is released when the roller is shifted back during the of the pathway race. Yet another approach does not use the spring in any way to retain the roller, as shown in co-assigned U.S. Pat. No. 4,821,856 to Lederman. Instead, dedicated roller control cars hold each roller, and the cars travel back and forth, with the rollers, in tracks on the cage side rails. Still another approach, shown in co-assigned U.S. Pat. No. 4,901,834 to Lederman, uses resilient projections on the side cage side rails that fit into end depressions on the rollers to hold the rollers during shipping. The roller latches are released by the same ringing in motion that releases the spring latches in U.S. Pat. No. 4,724,940.